I have a W124 300-E 1989 that recently has developed a hard starting problem when cold. I have to coach the throttle several minutes before it will warm up . Other wise it will sputter and shut down with out goosing the throttle. When it is almost at operating tempture than it runs smoothly on its own. the car is stock and has no modifications.

What do I check out ?

Thank You
Krwaxbz

The EHA would be a good place to start, i had a same problem as you(but not as severe) and turns out it was a leaky EHA. if you do a search you can find out alot about it.

Thank you for your reply could you give me the meaning of EHA so I can look in the factory manual for information on this part.

Thank You
Krwaxbz

Some kind of black square box on the back of the fuel distributor. Apparently it is the source of a gasoline smell in the morning under the hoods of MB's. Google it "eha mercedes"

Don't overlook the simple stuff. All last week my 300D (W123) was hard starting, stalling when cold, etc. I checked the glow plugs, looked at the pre-filter, etc. Finally, I needed fuel and filled up. The hard starting when away immediately. Then I remembered that I had filled up at a strange station the last time. I guess I just had a tank of "weak" fuel.

EHA = electrohydraulic actuator.

Check for vacuum leaks.

Cold motor needs richer than normal mixture, and vacuum leaks defeat the process.

Check especially the hose from valve cover to intake manifold.

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles